Campbell A J D, Croser E L, Milne M E, Hodge P J, Webb Ware J K
Faculty of Veterinary Science, University of Melbourne, 250 Princes Highway, Werribee, Victoria 3030, Australia.
Aust Vet J. 2012 Jun;90(6):235-9. doi: 10.1111/j.1751-0813.2012.00915.x. Epub 2012 Apr 11.
Several outbreaks of goitre, considered to be related to iodine deficiency, occurred in sheep flocks throughout Victoria in 2010.
We describe one outbreak in Merino-Border Leicester-cross ewes and their lambs in north-east Victoria that appeared to be associated with increased rainfall and pasture growth, particularly during the preceding summer and autumn.
The outbreak was characterised by a four-fold increase in neonatal lamb deaths and goitre, alopecia and poor skeletal development in the lambs. Most cases occurred in lambs born to 2-year-old crossbred ewes that had grazed long, lush perennial pastures throughout their entire pregnancy, whereas few cases occurred in mature crossbred or Merino ewes that had grazed shorter, annual pastures on hill country for 3 weeks in late pregnancy but were otherwise managed similarly.
Existing recommendations for south-eastern Australia are that only spring-lambing ewes in iodine-deficient areas require iodine supplementation to prevent goitre in years with high autumn-winter rainfall. Aspects of this outbreak suggest that ewes lambing at other times of the year and grazing abundant pasture for prolonged periods may also require supplementation to prevent goitre, even if autumn-winter rainfall does not exceed previously established thresholds.
2010年，维多利亚州各地的羊群中发生了几起被认为与碘缺乏有关的甲状腺肿疫情。
我们描述了维多利亚州东北部美利奴-边境莱斯特杂交母羊及其羔羊的一次疫情，该疫情似乎与降雨增加和牧草生长有关，尤其是在前一个夏季和秋季。
此次疫情的特征是新生羔羊死亡数量增加了四倍，且羔羊出现甲状腺肿、脱毛和骨骼发育不良的情况。大多数病例发生在2岁杂交母羊所生的羔羊身上，这些母羊在整个孕期都食用长而茂盛的多年生牧草，而在成熟杂交母羊或美利奴母羊所生的羔羊中病例较少，这些成熟母羊在怀孕后期在山区食用较短的一年生牧草3周，但其他管理方式相似。
澳大利亚东南部现有的建议是，只有碘缺乏地区春季产羔的母羊需要补充碘，以防止在秋冬降雨量高的年份出现甲状腺肿。此次疫情的一些情况表明，即使秋冬降雨量未超过先前设定的阈值，在一年中其他时间产羔且长时间食用丰富牧草的母羊可能也需要补充碘以预防甲状腺肿。
